H04M15/00—Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP
H04M15/28—Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP with meter at substation or with calculation of charges at terminal
G—PHYSICS
G04—HOROLOGY
G04F—TIME-INTERVAL MEASURING
G04F8/00—Apparatus for measuring unknown time intervals by electromechanical means
G04F8/08—Means used apart from the time-piece for starting or stopping same